Can anyone explain what this program is doing ! (Program is in attachment)
Code:#include<stdio.h> int main() { char s[]="No two viruses work similarly"; int i =0; while(s[i]!='\0'); { printf("%c %c\n",s[i],*(s+i)); printf("%c %c\n",i[s],*(i+s)); i++; } return 0; }
Last edited by Salem; 08-29-2014 at 03:05 PM. Reason: Inline the code
You should post the code here using code tags.
You might want to stare at line 6 some more, until you see a problem.
If you dance barefoot on the broken glass of undefined behaviour, you've got to expect the occasional cut.
If at first you don't succeed, try writing your phone number on the exam paper.
It took me almost two minutes to see it.Originally Posted by Salem
Tim S.
"...a computer is a stupid machine with the ability to do incredibly smart things, while computer programmers are smart people with the ability to do incredibly stupid things. They are,in short, a perfect match.." Bill Bryson
First, yes line 6's probably should've been picked up with your compiler.
But after fixing that, to answer your question, basically this program is showing you 4 ways an element of an array can be addressed.
The second two ways are not recommended though.
I understand the problem on line 6, but could someone please explain to me line 9's use ofwhen i is defined as an int ... how is it an array or subject to array notation (i.e. the 's' as a subscript)..???Code:i[s]
To understand this, refer to what the standard has to say about the definition of operator[]
i[s] is identical to (*((i)+(s))) which is equivalent to (*((s)+(i))) which is identical to s[i]. However, because most people would expect s[i] (and indeed the standard also states that "E1[E2] designates the E2-th element of E1 (counting from zero)", using i[s] is poor practice.
Look up a C++ Reference and learn How To Ask Questions The Smart Way
WOW... That is astounding.
Thank you for the great description,
and your description of it as "poor practice" is an understatement...
